As patients live longer and are diagnosed with chronic and often debilitating ailments, there is an increased need for improvements to the speed, convenience, and efficacy of drug delivery. For example, many chronic conditions, including multiple sclerosis, diabetes, osteoporosis, and Alzheimer's disease, are incurable and difficult to treat with currently available therapies: oral medications have systemic side effects; injections may require a medical visit, can be painful, and risk infection; and sustained-release implants must typically be removed after their supply is exhausted, and offer limited ability to change the dose in response to the clinical picture. In recent decades, several types of wearable drug delivery devices have been developed, including battery-powered miniature pumps, implantable drug dispensers, and diffusion-mediated skin patches.
Treatments for a number of chronic diseases currently require subcutaneous administration of a drug or therapeutic agent either continuously or at specific times or time intervals in highly controlled doses. Subcutaneous injections take advantage of the lack of blood flow to the subcutaneous layer, which allows the administered drug to be absorbed more slowly over a longer period of time (compared with direct injection into the blood stream). Additional advantages to subcutaneous delivery of some drugs (i.e., vaccines, tuberculin tests, immunostimulents, etc.) to the tissue region are the targeting of lymph tissue and lymphatic drainage for subsequent antigen presentation to the body. Traditionally, these types of injections have been administered either by the patient or a medical practitioner anywhere from several times a day to once every few weeks. Such frequent injections can result in discomfort, pain, and inconvenience to the patient.
Small, wearable, battery-powered drug pump devices capable of delivering controlled dosages of drug continuously or at specified times (dependent on the needs of the patient) to a catheter that remains inserted in subcutaneous tissue solve some of these problems. These pumps may, in principle, be turned on and off manually, e.g., by pushing a toggle switch. In some applications, however, the pumps may be implanted or adhere the patient's skin at a location that is inaccessible or inconvenient to reach. For example, certain ophthalmic pump devices are, in use, placed on the patient's eyeball underneath or behind the eyelid. Furthermore, certain drug regimens require complicated drug-delivery protocols, which may change over time depending on patient response. In such circumstances, self-administration can pose a significant risk of non-compliance or errors in dosage events. Visits to a clinician for the purpose of controlling pump operation in accordance with the protocol, on the other hand, may be impractical or inconvenient. Accordingly, there is a need for systems and methods that facilitate remote control of implantable or wearable drug pump devices and, desirably, the execution of drug delivery protocols without the need for human intervention in device operation.